I'm not sure if the "file" command supports the -b option on all platforms. It seems like platform used file -b in the past and nobody complained.

@serhiy-storchaka: you wrote PR #11160, but I'm confident that it will be fine to use "file -b -- executable" command. I propose to make this change in the master branch and leave stable branches (2.7 and 3.7) unchanged. If something goes wrong, we can easily revert this change.

Could you then borrow other changes from #11160?

I removed "--" from "file -b -- target". If target starts with "-", file will fail since the filename miss. Example:

$ file -b -b
Usage: file [-bcCdEhikLlNnprsvzZ0] [--apple] [--extension] [--mime-encoding]
            [--mime-type] [-e <testname>] [-F <separator>]  [-f <namefile>]
            [-m <magicfiles>] [-P <parameter=value>] <file> ...
       file -C [-m <magicfiles>]
       file [--help]

$ echo $?
1

This change should prevent portability issue.

Could you then borrow other changes from #11160?

Sure. I picked your changes into my PR and I credited you.

I replaced env={'LC_ALL': 'C'} with env=dict(os.environ, LC_ALL='C'). Few programs like to run in an (almost) empty environment.

I wasn't sure if you preferred to push your changes separately or not.

I propose to not backport this fix. At least not the addition of the -b flag.